METTL3-m6A methylation inhibits the proliferation and viability of type II alveolar epithelial cells in acute lung injury by enhancing the stability and translation efficiency of Pten mRNA.

BACKGROUND: The pathogenesis of acute lung injury (ALI) involves a severe inflammatory response, leading to significant morbidity and mortality. N6-methylation of adenosine (m6A), an abundant mRNA nucleotide modification, plays a crucial role in regulating mRNA metabolism and function. However, the precise impact of m6A modifications on the progression of ALI remains elusive. METHODS: ALI models were induced by either intraperitoneal injection of lipopolysaccharide (LPS) into C57BL/6 mice or the LPS-treated alveolar type II epithelial cells (AECII) in vitro. The viability and proliferation of AECII were assessed using CCK-8 and EdU assays. The whole-body plethysmography was used to record the general respiratory functions. M6A RNA methylation level of AECII after LPS insults was detected, and then the "writer" of m6A modifications was screened. Afterwards, we successfully identified the targets that underwent m6A methylation mediated by METTL3, a methyltransferase-like enzyme. Last, we evaluated the regulatory role of METTL3-medited m6A methylation at phosphatase and tensin homolog (Pten) in ALI, by assessing the proliferation, viability and inflammation of AECII. RESULTS: LPS induced marked damages in respiratory functions and cellular injuries of AECII. The m6A modification level in mRNA and the expression of METTL3, an m6A methyltransferase, exhibited a notable rise in both lung tissues of ALI mice and cultured AECII cells subjected to LPS treatment. METTL3 knockdown or inhibition improved the viability and proliferation of LPS-treated AECII, and also reduced the m6A modification level. In addition, the stability and translation of Pten mRNA were enhanced by METTL3-mediated m6A modification, and over-expression of PTEN reversed the protective effect of METTL3 knockdown in the LPS-treated AECII. CONCLUSIONS: The progression of ALI can be attributed to the elevated levels of METTL3 in AECII, as it promotes the stability and translation of Pten mRNA through m6A modification. This suggests that targeting METTL3 could offer a novel approach for treating ALI.

MSCs-derived extracellular vesicles alleviate sepsis-associated liver dysfunction by inhibiting macrophage glycolysis-mediated inflammatory response.

Sepsis-associated liver dysfunction (SALD) aggravates the disease progression and prognosis of patients. Macrophages in the liver play a crucial role in the occurrence and development of SALD. Human umbilical cord mesenchymal stem cells (MSCs), by secreting extracellular vesicles (EVs), show beneficial effects in various inflammatory diseases. However, whether MSC-derived EVs (MSC-EVs) could ameliorate the inflammatory response in liver macrophages and the underlying mechanisms remain unclear. In this study, a mouse model of sepsis induced by lipopolysaccharide (LPS) challenge was used to investigate the immunomodulatory functions of MSC-EVs in SALD. LPS-stimulated primary Kupffer cells (KCs) and Raw264.7 were used to further explore the potential mechanisms of MSC-EVs in regulating the inflammatory response of macrophages. The results showed that MSC-EVs alleviated liver tissue injury and facilitated the polarization of M1 to M2 macrophages. Further in vitro studies confirmed that MSC-EVs treatment significantly downregulated the expression of several enzymes related to glycolysis and reduced the glycolytic flux by inhibiting hypoxia-inducible factor 1α (HIF-1α) expression, thus effectively inhibiting the inflammatory responses of macrophages. These findings reveal that the application of MSC-EVs might be a potential therapeutic strategy for treating SALD.

Th9/IL-9 may participate in the pathogenesis of multiple myeloma.

INTRODUCTION: This research is aimed to evaluate the correlation between Th9-associated cytokine levels in MM patients, clinical features, and therapy. METHODS: Peripheral blood samples were taken in 52 MM patients and 20 healthy volunteers matched by sex and age. The patients with MM were separated into two groups: the untreated group (27) and the remission group (25). An enzyme-linked immunosorbent assay (ELISA) was used to measure the IL-9 plasma levels. The levels of Th9-associated cytokines' mRNA expression (IL-9, PU.1, and IRF4) were measured in RT-qPCR. We also analyzed the correlations between the IL-9 plasma levels and the clinical parameters of newly diagnosed MM patients. RESULTS: The IL-9 plasma levels and the Th9-associated cytokines (IL-9, PU.1, and IRF4) mRNA levels in newly diagnosed MM patients were significantly elevated than those in healthy volunteers and significantly decreased after achieving remission. Moreover, PU.1 and IRF4 had a positive correlation with the IL-9 mRNA expression. Then, we found that the upregulation of IL-9 plasma levels correlates with the severity of anemia and decreased albumin Levels. CONCLUSION: The results demonstrate that Th9/IL-9 may be involved in the pathogenesis of MM and is correlated with worse patient conditions such as lower hemoglobin and serum albumin. More work is necessary to confirm whether they might serve as a useful therapeutic target and prognostic marker for MM.

Density Functional Theory and Raman Spectroscopy Studies of Adsorption Sites of Au Nanoparticles with Alectinib.

Alectinib is an ALK tyrosine kinase inhibitor, which is mainly used in patients with crizotinib-resistant nonsmall cell lung cancer. Alectinib has attracted much clinical attention for its longest progression-free survival time and the best therapeutic effect. The chemical adsorption of Au nanoclusters (AuNPs) with alectinib molecules is studied by density functional theory (DFT) and surface-enhanced Raman scattering spectroscopy (SERS) experiments. DFT/B3LYP-D3/6-311G** was used for optimization and vibration analysis of alectinib-Au6 complexes, as well as molecular electrostatic potential, frontier molecular orbital, and electro-optic-based charge transfer descriptors. Comparing the results of the DFT theory and SERS experiment, alectinib and AuNPs can form Au-N6 bonds primarily through chemical adsorption of N6 atoms, and the experimental results showed that the enhancement factor (EFCHEM) could reach 4.27. The results provide a theoretical basis for exploring the mechanism of chemical enhancement between AuNPs and alectinib.

Liposome-encapsulated curcumin attenuates HMGB1-mediated hepatic inflammation and fibrosis in a murine model of Wilson's disease.

BACKGROUND AND AIMS: Wilson's disease (WD) is an inherited disorder of copper metabolism with predominant hepatic manifestations. Left untreated, it can be fatal. Current therapies focus on treating copper overload rather than targeting the pathophysiology of copper-induced liver injuries. We sought to investigate whether liposome-encapsulated curcumin (LEC) could attenuate the underlying pathophysiology of WD in a mouse model of WD. APPROACH AND RESULTS: Subcutaneous administration in a WD mouse model with ATP7B knockout (Atp7b-/-) resulted in robust delivery of LEC to the liver as determined by in-vitro and in-vivo imaging. Treatment with LEC attenuated hepatic injuries, restored lipid metabolism and decreased hepatic inflammation and fibrosis, and thus hepatosplenomegaly in Atp7b-/- mice. Mechanistically, LEC decreased hepatic immune cell and macrophage infiltration and attenuated the hepatic up-regulation of p65 by preventing cellular translocation of high-mobility group box-1 (HMGB-1). Moreover, decreased translocation of HMGB1 was associated with reduced splenic CD11b+/CD43+/Ly6CHi inflammatory monocyte expansion and circulating level of proinflammatory cytokines. Nevertheless there was no change in expression of oxidative stress-related genes or significant copper chelation effect of LEC in Atp7b-/- mice. CONCLUSION: Our results indicate that treatment with subcutaneous LEC can attenuate copper-induced liver injury in an animal model of WD via suppression of HMGB1-mediated hepatic and systemic inflammation. These findings provide important proof-of-principle data to develop LEC as a novel therapy for WD as well as other inflammatory liver diseases.

Targeting Glucose Metabolism Sensitizes Pancreatic Cancer to MEK Inhibition.

Pancreatic ductal adenocarcinoma (PDAC) is almost universally lethal. A critical unmet need exists to explore essential susceptibilities in PDAC and to identify druggable targets to improve PDAC treatment. KRAS mutations dominate the genetic landscape of PDAC and lead to activation of multiple downstream pathways and cellular processes. Here, we investigated the requirement of these pathways for tumor maintenance using an inducible KrasG12D -driven PDAC mouse model (iKras model), identifying that RAF-MEK-MAPK signaling is the major effector for oncogenic KRAS-mediated tumor maintenance. However, consistent with previous studies, MEK inhibition had minimal therapeutic effect as a single agent for PDAC in vitro and in vivo. Although MEK inhibition partially downregulated transcription of glycolysis genes, it failed to suppress glycolytic flux in PDAC cells, which is a major metabolic effector of oncogenic KRAS. Accordingly, an in vivo genetic screen identified multiple glycolysis genes as potential targets that may sensitize tumor cells to MEK inhibition. Inhibition of glucose metabolism with low-dose 2-deoxyglucose in combination with a MEK inhibitor induced apoptosis in KrasG12D -driven PDAC cells in vitro. The combination also inhibited xenograft PDAC tumor growth and prolonged overall survival in a genetically engineered PDAC mouse model. Molecular and metabolic analyses indicated that co-targeting glycolysis and MAPK signaling results in apoptosis via induction of lethal endoplasmic reticulum stress. Together, our work suggests that combined inhibition of glycolysis and the MAPK pathway may serve as an effective approach to target KRAS-driven PDAC. SIGNIFICANCE: This study demonstrates the critical role of glucose metabolism in resistance to MAPK inhibition in KRAS-driven pancreatic cancer, uncovering a potential therapeutic approach for treating this aggressive disease.

Effect of adenosine monophosphate-activated protein kinase-p53-Krüppel-like factor 2a pathway in hyperglycemia-induced cardiac remodeling in adult zebrafish.

AIMS/INTRODUCTION: Diabetic cardiomyopathy is a type of myocardial disease. It causes left ventricular hypertrophy, followed by diastolic and systolic dysfunction, eventually leading to congestive heart failure. However, the underlying mechanism still requires further elucidation. MATERIALS AND METHODS: A high-glucose zebrafish model was constructed by administering streptozocin intraperitoneally to enhance the development of cardiomyopathy and then treated with adenosine monophosphate-activated protein kinase (AMPK) activator. Cardiac structure and function, and protein and gene expression were then analyzed. Cardiomyocytes (CMs) culture in vitro using lentivirus were used for detection of AMPK, p53 and Krüppel-like factor 2a (klf2a) gene expression. RESULTS: In the hyperglycemia group, electrocardiogram findings showed arrhythmia, echocardiography results showed heart enlargement and dysfunction, and many differences, such as increased apoptosis and myocardial fiber loss, were observed. The phospho-AMPK and klf2a expression were downregulated, and p53 expression was upregulated. Activation of phospho-AMPK reduced p53 and increased klf2a expression, alleviated apoptosis in CMs and improved cardiac function in the hyperglycemic zebrafish. In vitro knockdown system of AMPK, p53 and klf2a using lentivirus illustrated an increased p53 expression and decreased klf2a expression in CMs by inhibiting AMPK. Repression of p53 and upregulation of klf2a expression were observed, but no changes in the expression of AMPK and its phosphorylated type. CONCLUSIONS: In the model of streptozocin-induced hyperglycemia zebrafish, the reduction of phosphorylated AMPK increased p53, which led to KLF2a decrease to facilitate apoptosis of CMs, inducing the cardiac remodeling and cardiac dysfunction. These results can be reversed by AMPK activator, which means the AMPK-p53-klf2a pathway might be a potential target for diabetic cardiomyopathy intervention.

Simultaneously Performed, Totally Endoscopic Left Atrial Myxoma Resection and Lobectomy.

The patient was a 69-year-old male patient with cancer in the right lung and whose preoperative examination showed left atrial myxoma. Simultaneous surgery for both cardiac myxoma resection and a lobectomy by totally endoscopic surgery without robotic assistance was performed. First, the cardiac tumor on the heart was removed using a cardiopulmonary bypass (CPB), then a lobectomy without any new incisions was performed. This case provides evidence that in individual select patients, a left atrial myxoma resection and lobectomy can be performed under total endoscopy at the same time.

Effects of inclusion level and amino acid supplementation on energy values of soybean oil determined with difference or regression methods in growing pigs.

OBJECTIVE: This study was conducted to evaluate the effects of inclusion level and amino acid (AA) supplementation on energy values of soybean oil (SO) as determined by difference method or regression method when fed to growing pigs. METHODS: Thirty-six barrows (initial BW: 28.0 ± 1.3 kg) were randomly assigned to one of 6 dietary treatments, which included 2 control diets formulated using a basal diet with or without AA supplementation, and 4 experimental diets with 5% or 10% SO addition in the 2 control diets, respectively. All pigs were individually housed in metabolism crates for 19 d, and during the last 5 d, total urine and feces production were collected. The nutrient digestibility in diets and the digestible energy (DE) and metabolizable energy (ME) values of SO were determined using the difference method and the regression method, respectively. RESULTS: Our results showed that there were no interaction effects (p > 0.05) between AA supplementation and SO inclusion levels on energy values of SO and dietary nutrient digestibility. The DE and ME values of SO determined by the difference method were not affected (p > 0.05) by AA supplementation, however, the ME value of SO increased (p < 0.05) as the inclusion level of SO increased. Moreover, the energy values of SO determined using the regression method were close to those determined using difference method with 10% SO inclusion, but were greater than those obtained using difference method with 5% SO inclusion. CONCLUSION: We concluded that the DE and ME values of SO increased with the inclusion level but were not affected by AA supplementation in the range of 0% to 10%. The difference method can substitute for the regression method to determine the DE and ME values of SO when the inclusion level is 10%, but not at 5% inclusion level.

YAP1 oncogene is a context-specific driver for pancreatic ductal adenocarcinoma.

Transcriptomic profiling classifies pancreatic ductal adenocarcinoma (PDAC) into several molecular subtypes with distinctive histological and clinical characteristics. However, little is known about the molecular mechanisms that define each subtype and their correlation with clinical outcome. Mutant KRAS is the most prominent driver in PDAC, present in over 90% of tumors, but the dependence of tumors on oncogenic KRAS signaling varies between subtypes. In particular, the squamous subtype is relatively independent of oncogenic KRAS signaling and typically displays much more aggressive clinical behavior versus the progenitor subtype. Here, we identified that yes-associated protein 1 (YAP1) activation is enriched in the squamous subtype and associated with poor prognosis. Activation of YAP1 in progenitor subtype cancer cells profoundly enhanced malignant phenotypes and transformed progenitor subtype cells into squamous subtype. Conversely, depletion of YAP1 specifically suppressed tumorigenicity of squamous subtype PDAC cells. Mechanistically, we uncovered a significant positive correlation between WNT5A expression and YAP1 activity in human PDAC and demonstrated that WNT5A overexpression led to YAP1 activation and recapitulated a YAP1-dependent but Kras-independent phenotype of tumor progression and maintenance. Thus, our study identifies YAP1 oncogene as a major driver of squamous subtype PDAC and uncovers the role of WNT5A in driving PDAC malignancy through activation of the YAP pathway.

Syndecan 1 is a critical mediator of macropinocytosis in pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) remains recalcitrant to all forms of cancer treatment and carries a five-year survival rate of only 8%1. Inhibition of oncogenic KRAS (hereafter KRAS*), the earliest lesion in disease development that is present in more than 90% of PDACs, and its signalling surrogates has yielded encouraging preclinical results with experimental agents2-4. However, KRAS*-independent disease recurrence following genetic extinction of Kras* in mouse models anticipates the need for co-extinction strategies5,6. Multiple oncogenic processes are initiated at the cell surface, where KRAS* physically and functionally interacts to direct signalling that is essential for malignant transformation and tumour maintenance. Insights into the complexity of the functional cell-surface-protein repertoire (surfaceome) have been technologically limited until recently and-in the case of PDAC-the genetic control of the function and composition of the PDAC surfaceome in the context of KRAS* signalling remains largely unknown. Here we develop an unbiased, functional target-discovery platform to query KRAS*-dependent changes of the PDAC surfaceome, which reveals syndecan 1 (SDC1, also known as CD138) as a protein that is upregulated at the cell surface by KRAS*. Localization of SDC1 at the cell surface-where it regulates macropinocytosis, an essential metabolic pathway that fuels PDAC cell growth-is essential for disease maintenance and progression. Thus, our study forges a mechanistic link between KRAS* signalling and a targetable molecule driving nutrient salvage pathways in PDAC and validates oncogene-driven surfaceome annotation as a strategy to identify cancer-specific vulnerabilities.

Insights into cellular metabolic pathways of the combined toxicity responses of Caco-2 cells exposed to deoxynivalenol, zearalenone and Aflatoxin B1.

Metabolic profiling in Caco-2 cells was studied for the combined toxic effects of deoxynivalenol (DON), zearalenone (ZEN), and Aflatoxin B1 (AFB1) through untargeted GC-MS. The GC-MS spectra of Caco-2 cells treated with individual 6.7 µM DON, 20 µM ZEN, 20 µM AFB1 and the combined DON + AFB1 (6.7 + 20 µM) and DON + ZEN + AFB1 (6.7 + 20 + 20 µM) for 24 h were deconvoluted, aligned and identified with MS DIAL. The metabolic pathway analysis was analyzed with MetaMapp and visualized with CytoScape. Results show that the combined DON + AFB1 and DON + ZEN + AFB1 treatment has an obvious "synergistic effect". The apoptosis-related gene mRNA test result indicates that the combined mycotoxins downregulate Bcl-2 gene and upregulate Bax, p53, caspase-3, caspase-8 and caspase-utilized 9 genes, more significantly than any individual mycotoxins group. The cellular metabolism illustrated that the combined mycotoxin groups, DON + ZEN + AFB1 seriously effect glycine, serine and threonine metabolism, pyruvate metabolism, etc. while no metabolic disorders were presented in individual mycotoxin group. Our hypothesis was validated that the combined mycotoxins with low concentrations can have a synergistic effect in the metabolism, which may lead to cellular apoptosis or necrosis.

MALAT1 promoted cell proliferation and migration via MALAT1/miR-155/MEF2A pathway in hypoxia of cardiac stem cells.

Accumulating evidence revealed that hypoxia contributed to many human diseases, including ischemic myocardium and heart failure (HF). In recent years, the roles of hypoxia in stem cell survival and cardiac biology have been studied extensively. However, the underlying molecular mechanisms remain to be elucidated. As a leading cause of HF, ischemic heart disease was correlated with hypoxia. In this study, we firstly constructed the hypoxia cell model by CoCl2 in cardiac stem cells (CSCs) and found that hypoxia induced the cell proliferation and migration potential in CSCs. Then, we demonstrated that the expression of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) was promoted in CoCl2 -induced CSCs hypoxia model. Furthermore, we found that knockdown of MALAT1 inhibited the cell proliferation and migration in CoCl2 -induced CSCs hypoxia model. In addition, we revealed that MALAT1 regulated the microRNA-155 (miR-155) expression in CSCs under both the normal and hypoxia conditions and further, manipulation of the miR-155 expression affected the role of MALAT1 in CoCl2 -induced CSCs hypoxia cell model. We then illustrated that miR-155 regulated the myocyte enhancer factor 2A (MEF2A) expression in CSCs under both the normal and hypoxia conditions and further, changing the expression of MEF2A affected the role of miR-155. Finally, we demonstrated that MALAT1 regulated the MEF2A expression and exerted its role via modulation of the MALAT1/miR-155/MEF2A pathway. Taken together, our study illustrated that MALAT1 promoted the cell proliferation and migration in CoCl2 -induced CSCs hypoxia model, acting mechanistically by promoting MEF2A expression via "sponging" miR-155.

Activation of the Nkx2.5-Calr-p53 signaling pathway by hyperglycemia induces cardiac remodeling and dysfunction in adult zebrafish.

Hyperglycemia is an independent risk factor for diabetic cardiomyopathy in humans; however, the underlying mechanisms have not been thoroughly elucidated. Zebrafish (Danio rerio) was used in this study as a novel vertebrate model to explore the signaling pathways of human adult cardiomyopathy. Hyperglycemia was induced by alternately immersing adult zebrafish in a glucose solution or water. The hyperglycemic fish gradually exhibited some hallmarks of cardiomyopathy such as myocardial hypertrophy and apoptosis, myofibril loss, fetal gene reactivation, and severe arrhythmia. Echocardiography of the glucose-treated fish demonstrated diastolic dysfunction at an early stage and systolic dysfunction at a later stage, consistent with what is observed in diabetic patients. Enlarged hearts with decreased myocardial density, accompanied by decompensated cardiac function, indicated that apoptosis was critical in the pathological process. Significant upregulation of the expression of Nkx2.5 and its downstream targets calreticulin (Calr) and p53 was noted in the glucose-treated fish. High-glucose stimulation in vitro evoked marked apoptosis of primary cardiomyocytes, which was rescued by the p53 inhibitor pifithrin-µ. In vitro experiments were performed using compound treatment and genetically via cell infection. Genetically, knockout of Nkx2.5 induced decreased expression of Nkx2.5, Calr and p53 Upregulation of Calr resulted in increased p53 expression, whereas the level of Nkx2.5 remained unchanged. An adult zebrafish model of hyperglycemia-induced cardiomyopathy was successfully established. Hyperglycemia-induced myocardial apoptosis was mediated, at least in part, by activation of the Nkx2.5-Calr-p53 pathway in vivo, resulting in cardiac dysfunction and hyperglycemia-induced cardiomyopathy.

Oligosaccharides are a key factor in prediction of amino acid digestibility in soybean meal of different origins when fed to growing pigs.

OBJECTIVE: The objective of this experiment was to determine apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of crude protein (CP) and amino acid (AA) in 15 sources of soybean meal (SBM) produced from soybeans from different countries and subsequently to establish equations for predicting the AID and SID in SBM based on their chemical composition. METHODS: Eighteen barrows (57.9±6.1 kg) fitted with a simple T-cannula were allotted into three 6×6 Latin square designs. Each period comprised a 6-d adaption period followed by a 2-d collection of ileal digesta. The 15 test diets included SBM as a sole source of AA in the diet. Another nitrogen-free diet was used to measure basal endogenous losses of CP and AA. Chromic oxide (0.3%) was used as an inert marker in each diet. RESULTS: The AID of lysine in SBM from China and USA tended to be greater than in SBM from Brazil (p<0.10). The SID of valine and proline in SBM from China was greater than in SBM from Brazil (p<0.05). The SID of lysine, threonine, cysteine and glycine in SBM from China tended to be greater than in SBM from Brazil (p<0.10). From a stepwise regression analysis, a series of AID and SID prediction equations were generated. The best fit equations for lysine in SBM were: AID lysine = 1.16 sucrose-1.81 raffinose+82.10 (R2 = 0.69, p<0.01) and SID lysine = 1.14 sucrose-1.93 raffinose-0.99 ether extract (EE)+85.26 (R2 = 0.77, p<0.01). CONCLUSION: It was concluded that under the conditions of this experiment, the oligosaccharides (such as sucrose and raffinose) can be used to predict the AID and SID of AA in SBM with reasonable accuracy.

Yap1 activation enables bypass of oncogenic Kras addiction in pancreatic cancer.

Activating mutations in KRAS are among the most frequent events in diverse human carcinomas and are particularly prominent in human pancreatic ductal adenocarcinoma (PDAC). An inducible Kras(G12D)-driven mouse model of PDAC has established a critical role for sustained Kras(G12D) expression in tumor maintenance, providing a model to determine the potential for and the underlying mechanisms of Kras(G12D)-independent PDAC recurrence. Here, we show that some tumors undergo spontaneous relapse and are devoid of Kras(G12D) expression and downstream canonical MAPK signaling and instead acquire amplification and overexpression of the transcriptional coactivator Yap1. Functional studies established the role of Yap1 and the transcriptional factor Tead2 in driving Kras(G12D)-independent tumor maintenance. The Yap1/Tead2 complex acts cooperatively with E2F transcription factors to activate a cell cycle and DNA replication program. Our studies, along with corroborating evidence from human PDAC models, portend a novel mechanism of escape from oncogenic Kras addiction in PDAC.

Structure-function analysis of barley NLR immune receptor MLA10 reveals its cell compartment specific activity in cell death and disease resistance.

Plant intracellular immune receptors comprise a large number of multi-domain proteins resembling animal NOD-like receptors (NLRs). Plant NLRs typically recognize isolate-specific pathogen-derived effectors, encoded by avirulence (AVR) genes, and trigger defense responses often associated with localized host cell death. The barley MLA gene is polymorphic in nature and encodes NLRs of the coiled-coil (CC)-NB-LRR type that each detects a cognate isolate-specific effector of the barley powdery mildew fungus. We report the systematic analyses of MLA10 activity in disease resistance and cell death signaling in barley and Nicotiana benthamiana. MLA10 CC domain-triggered cell death is regulated by highly conserved motifs in the CC and the NB-ARC domains and by the C-terminal LRR of the receptor. Enforced MLA10 subcellular localization, by tagging with a nuclear localization sequence (NLS) or a nuclear export sequence (NES), shows that MLA10 activity in cell death signaling is suppressed in the nucleus but enhanced in the cytoplasm. By contrast, nuclear localized MLA10 is sufficient to mediate disease resistance against powdery mildew fungus. MLA10 retention in the cytoplasm was achieved through attachment of a glucocorticoid receptor hormone-binding domain (GR), by which we reinforced the role of cytoplasmic MLA10 in cell death signaling. Together with our data showing an essential and sufficient nuclear MLA10 activity in disease resistance, this suggests a bifurcation of MLA10-triggered cell death and disease resistance signaling in a compartment-dependent manner.